Introduction
Underwater exploration is the exploration of any underwater environment by remote observation and measurement, either by the explorer going underwater or under the guidance of investigators. Accordingly, underwater exploration is the most effective way to increase understanding of oceans and other underwater areas so that they can be effectively managed, conserved, regulated, and their resources discovered, accessed, and used. Oceans can be divided into deep oceans and coastal waters. Inland water is mostly fresh and consists of rivers, lakes, and groundwater, some of which is in accessible caves. Less than 10% of the ocean has been mapped in any detail, much less visually monitored, and overall biodiversity and population distribution are similarly unclear.
Exploration includes the investigation of the body of water or its form and size, the investigation of the geological features of the seabed and fresh water-like materials, and the investigation of the geological structure, strata, and sediments underlying the body of water. The physical and environmental characteristics of water and its geographical features, the discovery and investigation of shipwrecks and archaeological sites, and direct and remote visual observation of its contents. Underwater exploration is a relatively recent development, as it relies heavily on relatively advanced technology in all related areas. depends on
Purposes
Underwater exploration involves measuring the distribution and diversity of marine and aquatic life, the geographic distribution of chemical and physical properties, including the movement of water, and the geophysical, geological, and geological features that cover Earth’s surface. Targeted exploration, respectively, is the most effective way to increase understanding of oceans and other underwater areas, so they can be effectively managed, conserved, exploited, and their resources discovered, accessed, and used. The ocean covers about 70% of the Earth’s surface and plays a critical role in supporting life on the planet, but knowledge and understanding of the ocean is limited due to the difficulty and cost of access.
The process of exploration
This does not require the explorer to be at the site of investigation and therefore involves going underwater and exploring the environment with remotely operated equipment and automated devices programmed to explore the underwater environment. Especially when the findings are published in some way for the benefit of the wider community. Some of the results of systematic exploration have been withheld from the general public for commercial and political reasons.
Traveling to those places to search for discoveries is too expensive for most people and organizations. These expeditions are mostly undertaken by the wealthy. When financial support is involved, investigations become systematic and targeted. A find from this mine tends to be presented only when something obviously unusual is found and is likely to be published as news.
Types of underwater exploration
- Investigation of the form and extent of the body of water or part thereof. (oceanography)
- Remote acoustic and satellite sensing, radar altimeters
- Sonar, high resolution and multibeam
- Direct measurement by divers of cave and reef structure using depth gauge, compass, clinometer, surveyor’s tape, hand-held sonar, and other instruments where applicable.
- Investigation of the geological characteristics of the seabed and freshwater equivalents, and through-ground investigation of the geological structure, strata, and sediments.
- Investigation of the physical and ecological characteristics of the body of water and its geographical features.
- Identification and recording of numbers and distribution of biological specimens
- Collection of biological samples by divers, grabs, nets, dredges, and manned and unmanned submersibles
- Infra-red and microwave radiometers for sea surface temperature measurement
- Bottom sampling: Grabs, dredges, gravity core sampler, piston corer, hydraulic piston corer [2] core drill
- Measurement and recording of the physical and chemical characteristics if the water
- Discovery and investigation of shipwrecks and archeological sites
- Magnetometer, multibeam sonar
- Direct and remote visual observation
- Divers and crewed observation submersibles, remotely operated underwater vehicles and autonomous underwater vehicles, video and still photography.
Lakes and rivers
Lake exploration is conducted in the same way as coastal water exploration, often simplified by the relatively small water movement and shallow depth, but it can easily extend beyond the range for deep atmospheric pressure diving. Visibility ranges between, at best, close to the theoretical maximum for water and, at worst, effectively zero or measurable in millimeters.
Rivers have complications in flow that can range from slow to fast and extremely turbulent, but are relatively shallow. Many lakes and rivers are relatively easily accessible, while others are in inaccessible locations.
Underwater diving
Divers are limited in mobility and range but can interact directly with the environment, which gives them great flexibility and precision of interaction, but they are not inherently efficient for precise measurement of the broader environment, for which they need tools and recording equipment.
History
The Challenger Expedition of 1872–76 was the first major marine expedition, whose primary purpose was to find deep-sea life using dredges and nets and to make physical, oceanographic, and chemical measurements of the marine environment.
Mapping of the ocean floor accelerated after World War II, when sonar technology enabled rapid depth measurements. The first comprehensive map of the world’s ocean floor was published in 1977 by geologists Marie Tharp and Bruce Heezen of the Lamont Geological Laboratory at Columbia University in New York, a collaboration that lasted from the 1950s to the 1970s. In the 1980s, William Haxby used satellite measurements to provide more information and gravity field data to provide a low-resolution map of the global seafloor.
The mass distribution of seafloor topography affects local gravity sufficiently for satellite radar altimeters to record changes in sea surface height, which can be used to approximate underwater topography. Using this data, the map created in 2014 revealed a large number of previously unknown seamounts, with almost double the resolution of the previous map created 20 years ago. Data from the European Space Agency’s (ESA) CryoSat-2 satellite and NASA’s Jason-1 satellite were used.
The 2015 First World Ocean Assessment showed that the ocean is important for the entire planet’s climate and life support and that critical ocean systems are under threat, making ocean exploration and mapping a key ecological target for understanding.